In a communications network, network switches receive data at one of a set of input interfaces and forward the data on to one or more of a set of output interfaces. As a general matter, it is preferable that such switching devices operate as quickly as possible in order to maintain a high data rate. Switches are typically data link layer devices that enable multiple physical network (e.g., local area network (LAN) or wide area network (WAN)) segments to be interconnected into a single larger network. Switches forward and flood data traffic based on, for example, MAC addresses. In the most general sense, these types of networks transport data in the form of frames. A frame is a logical grouping of information sent as a data link layer unit over a transmission medium. Frames typically include header and/or trailer information used, for example, for routing, synchronization, and error control. The header and/or trailer information surrounds user data contained in the unit. The terms cell, datagram, message, packet and segment are also used to describe logical information groupings at various layers of the OSI reference model and in various technology circles. As used herein, the term “frame” should be understood in its broadest sense, and can encompass other terms such as cell, datagram, message, packet and segment.
A recent trend is to deploy blade servers within data centers, in place of more traditional servers. Blade servers generally have a modular chassis and a set of central processing unit (“CPU”) blades plugged into that chassis. In addition to CPU blades, there are typically two or more network interface blades. For instance, some of these network interface blades can be used for Fibre Channel (FC) connectivity, e.g., to a storage area network (SAN), while others could be used for Ethernet connectivity. The use of such blade servers provides numerous benefits, including greater rack density, simplified interconnect, and lower cost. For example, a typical blade server could include multiple blades, each of which can be interconnected with a number of different switches, all within a single chassis. To other devices in the network, each of blades can appear to be an individual device. Each of blades may provide, for example, the functionality of a server that is operating independently of the other blades within chassis. The Ethernet switches within the server could provide redundant connections with, e.g., a local area network and the Internet, while the FC switches could provide redundant connections with a SAN and various storage devices.